Once you are at the GZ, you're near the entrance to the ZZZZs. Walk across and walk around to enjoy the place!
The Cache
You'll find the following at the published coordinates:

Zoomed in:

The GPS is jumpy with all the buildings around.
The cache itself is located at:
N 22° 19.(C+2)(C+2)D
E 114° 12.DG(D-1)
You can check your answers for this puzzle on GeoChecker.com.
Something interesting about GZ: there seems to be a gate to keep wild boars in their place.
Note
- BYOP
- Beware of muggles!
- Please put it back exactly how you found it.
- If English is not your first language, look up the word post. It may just save you some head-scratching.